Should shaft brushes eliminate shaft zincs?

shaft wipers

In some cases yes in some cases no. You are driving 1/2 a volt @ 1/4 amp. The connection must be clean and maintained. Most low cost brush systems are nothing more than sintered oil-light bearings that have been cut in two and tooled to fit on a tensioned arm. The transmision connection is equally as unreliable. All metals film. What makes stainless steel stainless is that it films a clear coating. Take away the oxegen and stainless crevices. What makes things worse for the connection is the high chromium stainless steels. Aquamet 19 & 22. They like Aquamet in shafting because it doesnt crevice in the rubber bearings. Take away the oxegen and the s/s cant film. The film that forms is chromic oxide. Chromic oxide is dielectric. The oil in the sintered oil-light brush is dielectric. It doesnt take long for the connection to breakdown. Several manufactures produce a silver brush system. The oxide of silver is more conductive than silver itself. The nastier the connection the better. The brushes are silver graphite and the shaft is fitted with a 99.9 % brushing surface.